Different imaging devices utilize various types of replaceable consumable units. Each type of xerographic or electro-photographic device may have unique requirements such as specific compatible toner, size requirements necessary to fit into a specific printer, power consumption, interface with the printer and so forth. A typical replaceable consumable unit such as a toner cartridge contains many different components such as toner, the OPC drum, developer roller and so forth. In addition, these replaceable consumable units are not limited to just toner cartridges but may also include intermediary OPC drum assemblies. The replaceable consumable units will also vary between monochrome and color based devices. As technology continues to improve, there is no end in sight to the variations of replaceable consumable devices that will be necessary to interoperate with the new and improved xerographic devices.
Along with the moveable parts, printer manufacturers have also moved data down to the replaceable consumable unit. Initially in some toner cartridges, the Original Equipment Manufacturers (OEM's) devised a way of detecting cartridge specific information from the cartridge itself. This was done via a mechanical process. With electronic circuits becoming smaller, more efficient and able to perform various tasks, printers are increasingly moving additional data to the replaceable consumable units. For example, information such as operating voltage, cartridge serial number, manufacturing history, printer history, toner consumption, and remaining toner may be stored locally on the cartridge. This allows the information associated with a specific cartridge to move with the cartridge should it be transported from one printer to another. It also allows the manufacturer to track the cartridge during its lifetime.
One method of obtaining information from the replaceable consumable unit and storing it on the cartridge is outlined in U.S. Pat. No. 5,995,774 issued to Applegate, et al. The patent describes a method and apparatus for storing data corresponding to the amount of toner remaining in an electronic circuit located on a xerographic toner cartridge. This circuit is in electrical communication with the printer via electrical contacts. The printer determines the amount of toner remaining as a value and this value is converted into “bucket levels” stored inside the memory of the electronic circuit. The initial bucket level corresponding to the amount of toner remaining in a new cartridge is full, and over the life of the cartridge, this value would be decremented down accordingly. The electronic circuit is designed such that the bucket levels may only be decremented and never incremented. Thus when the replaceable consumable unit reaches an empty state, the printer would recognize that there was no toner remaining and would designate the bucket levels to be empty. Once the bucket level had been declared empty, the cartridge was spent and subsequently it needed to be replaced.
Once a used replaceable consumable unit such as a toner cartridge has depleted its supply of toner it may be recycled. An industry known as the remanufacturing industry has arisen to take advantage of this fact. Remanufacturers take the used replaceable consumable units, clean them, repair damaged components, replace worn out components, add new toner, and reintroduce these refurbished units into the marketplace. Some of the many components that the remanufacturers replace may include the PCR, OPC drum, magnetic roller, wiper blades, agitators, seals, encoder wheels, and electronic control circuitry just to name a few.
In order to protect its profitability, the OEM's designed the replaceable consumable unit to be a single use product. Once the product had reached the end of its life, the OEM anticipated that the consumer would discard the used part and replace it with a new replaceable consumable unit. Additionally, the OEM has ensured that the replaceable consumable units may not simply be refilled with toner, refurbished and placed back into service, by installing protection measures on the replaceable consumable unit. For example, several OEM's have installed a one-time writable electronic circuit onto the replaceable consumable unit itself. The imaging device has the ability to interface with this electronic circuitry and once this circuit has been disabled, the replaceable consumable unit ceases to function.
One advantage of the present invention is that it provides a way to repair these electronic circuits in the various replaceable consumable units once they have been disabled during their normal course of life. The invention allows a second electronic circuit to communicate with the printer in conjunction with the existing nonfunctional electronic circuit. By taking advantage of the existing circuit's ability to talk to the printer, the secondary circuit can perform the functions that the initial circuit has been disabled from performing. The non-functioning electronic circuit will be connected to a second electronic circuit so that the second electronic circuit will be able to intercept electrical signals intended for the non-functioning circuit. By monitoring the communications coming from the printer, the second electronic circuit will intercept, process and resend the data to the first circuit. The first circuit will respond accordingly and it will reply with the proper sequence of data. The interplay between these circuits is described in greater detail in a later section.
In the preferred embodiment, a microprocessor will be used. It will be able to determine when the specific locations corresponding to the toner level are being accessed and will subsequently use its own memory locations to store this information. Once the cartridge using the second electronic circuit has depleted all of the usable toner the printer will once more write the appropriate value in the correct location in memory and the printer will disable the ability to change this location. The cartridge is then sent back to be recycled.
Another aspect of the present invention is that it provides the flexibility for various methods of attaching the second circuit to the non-functioning electronic circuit. The location of the contacts of the second electronic circuit is dictated by the location of the electrical contacts of the printer. However, the actual location of the second electronic circuit itself may be anywhere on the replaceable consumable unit, as long as there is space for mounting of the circuit as well as electrical connectivity to the printer contacts.
Another aspect of the present invention is that it encompasses the use of a replacement electronic circuit. This replacement circuit will provide additional functionality that the original OEM circuit did not employ. For instance, the replacement circuit will have the ability to make the replaceable consumable unit more reliable by providing a back-up or alternative path for the communications to the printer. By designing the circuit with redundant paths, which can be changed on the fly, the circuit becomes more robust. When this occurs, the present invention will notify the user that an error condition was detected and that the communications path has been switched. These types of errors would be undetectable in the existing circuitry of the replaceable consumable device due to hardware limitations. In addition, the replacement circuit will make the replaceable consumable unit recycle friendly by having the ability to be reprogrammed by using a special reprogramming dongle. When the replacement circuitry has been disabled by the imaging device, a remanufacturing service technician will have the ability to reprogram the device without removing the replacement circuit from the replaceable consumable unit. This gives the remanufacturer increased flexibility when refurbishing the cartridge.
Another aspect of the present invention is the ability of the invention to modify the voltage potential being applied to some of the developer components of the replaceable consumable. Over time, as the imaging device creates thousands of printed copies of images, the voltage potential being applied to the developer components will vary. The goal is that once a certain amount of toner has been used, the replaceable consumable unit will alter the voltage potential such that the printer may use less toner, thus conserving the remaining toner.
Another type of replaceable consumable unit utilizes a wireless configuration to communicate between the circuitry on the replaceable consumable unit and the printer. In this type of application, the replaceable consumable unit is written to and read from in a comparable fashion as discussed previously. As well, the same type of information may be stored on the cartridge for the printer to monitor and update. Similarly, in this application, once the toner supply is exhausted, the printer writes into a specific location on the circuit and disables the circuitry.
Without the present invention, hundreds of thousands of used replaceable consumable units are being thrown away instead of being recycled simply due to the non-functional electronic circuit. The availability of new OEM electronic circuits is completely at the discretion of the OEM's. Given that the OEM's make a healthy profit from the sale of new replaceable consumable units, and receive no monetary benefit from a remanufactured replaceable consumable unit, it has been very difficult for the remanufacturing industry to obtain new electronic circuits. The use of these one-time writable circuits, which employ an exclusive communications protocol was an attempt by some of the OEM's to restrict the remanufacturing of its cartridges.